Method of refrigerator manufacture



May 6, 1930. L. G. COPEMAN METHOD OF REFRIGERATOR MANUFACTURE Filed Feb. 26. 1926 2 Sheets-Sheet l xxx M KMNKRNXQ y 6, 1930. 1.. G. COPEMAN 1,757,450

IETHOD 'GF REFRIGERATOR MANUFACTURE Filed Feb. 26. 1926 2 Sheets-Sheet 2 F j, INVENTOR.

gays

li'oyd fipammv Patented May 6, 1930 UNITED STATES,

PATENT OFFICE LLOYD G. COPEMAN, OF FLINT, MICHIGAN, ASSIGNOR TO COPEMAN LABORATORIES COMPANY, OF FLINT, MICHIGAN, "A CORPORATION OF MICHIGAN METHOD OF REFRIGERATOR MANUFACTURE Application filed February 26, 1926. Serial No. 91,000.

This invention relates to a method of refrigerator manufacture, and has to do particularly with the manufacture of moulded stone refrigerators and the forming and coating of the finished interior of such stone refrigerators.

In forming refrigerators and other similar articles of stone I have found'that a very compact, light and beautiful refrigerator, or other article can be made by casting such article of mouldedjstone formed preferably of "an oXy chloride cement, such for instance, as

a composition containing dry magnesium .powder, and a sand and ground fiint aggregation, or a combination of both. To this is added enough magnesium chloride solution to make the mix either plastic, or so that it will pour. Hitherto, these refrigerators have been cast or moulded by various different methods, some of which have contemplated thecasting of the refrigerator as a solid unit of stone,'others have contemplated the casting of the inner and outer shells separately to be subsequently combined, and still others have contemplated the forming of the reinforcing structure and the moulding or spraying of the plastic stone to the reinforcement or core. In the forming of most of these stone refrigerators it has been the practice to provide an inner core, or cores, for forming the interior chambers of the refrigerator. The core has been covered with a film of parting material, such as stearic acid, and the refrigerator, or inner walls of the refrigerator formed by casting the plastic stone around such core. The core has then been with 'drawn and it has then been necessary to completely remove the parting material from the interior of the-.cast refrigerator in order to apply the finishing coat of enamel. Regardless of the laborious task of completely removing the parting material from the stone it has also been a source of much trouble and expense to place the interior walls of the refrigerator in a condition for the reception of an enamel so as to present a smooth surface backed by a solid surface of stone.

I have discovered that the coating of the interior walls of the refrigerator can be accomplished by an entirely different method which entirely eliminates the necessity ofthe Workman preparing and finishing the cast inner Walls for the reception of the enamel. I have found that by first putting the enamel coating upon the core itself and then inserting the enameled core into the mould and then filling the mould with the plastic stone;

that upon setting and hardening the enameled surface upon the core will be directly transferred to the interior" stone walls of the refrigerator. This gives to the interior cavities of the refrigerator an absolutely smooth enameled finish, formed simultaneouslywith the casting operation.

In the drawings:

Fig.1 is a vertical section showing the mould and the enamel coated cores being inserted into position therein. a

Fig. 2 is a vertical section similar to Fig. 1 showing the enameled cores in place in the mould and the plastic stone poured into place to form the interior walls of the refrigerator.

Fig. 3 is a vertical section showing the cores being withdrawn after setting of the stone worlr, and also showing the manner of transferrmg the enameled outer surface of the cores to form the finished surface of the interior walls of the refrigerator.

Fig. 4 illustrates a preferred manner of applying a suitable filler to the'surface of the enameled core before inserting the same in the mould.

Fig. 5 is a detail section of a modified core embodying heating elements.

Any form of mould structure may be utilized in performing my novel method, and as shown in the drawings, the mould is shown as comprising an outer shell 1, which may be the outer wooden shell of the refrigerator itself, or the reinforcing or insulating material for receiving a cast or sprayed stone wall. To this wooden shell 1 is fitted, or glued, suitable cork boards 2. The cores for forming the interiorwalls of the refrigerator may be designated 3,and are preferably made of cement incasing a wooden framework 4.

Prior to inserting the cores in the mould I preferably apply suitable parting material enamel. may be any suitable air drying enamel such as fitiliied in finishing the interior of refrigerators. When the enamel has been,

applied to the surface of the core, a suitable primer, or filler is preferably applied to evenly cover the enameled surface of the core, as is best illustrated in Fig. 4'.

The cores having been covered with the enamel and filler they may be then inserted in the mould, as shown in Fig. 2 and plastic stone poured from the back so that the mix will'settle in its place between the cores and the cork board of the mould. After the plastic stone has hardened sufficiently, the cores ,may'beremoved inanysuitablemannerandthe filler and the enamel, initially applied to the core, will'have in the meantime adhered to, or combined with, the plastic stone, whereby such coatings of filler and enamel will have been transferred, from. the core ,to form the so interior finished walls of the refrigerator.

If any parting material remains on' the enameled surface it is immaterial, as it may be easily removed. The filler initially applied to the outside of the cores will be pressed as into any voids in the moulded stone, whereby the enameled coating" will. have a solid backing and present a smooth surface, regardless of any uneven spraying or application of enamel to the core.

In Fig. 5 I have shown the core provided with a suitable electric resistance element whereby the core may be heated as desired. When this form of heating core is used the settling action of the plastic stone may be effectively hastened and the transfer of the enameled shell from the core to the plastic stone may also be more effectively accomplished.

What I claim is:

whichconsists in applying a parting mate rial to the core, coating the core with an enamel or finishing material, placing the core in the. mould and pouring the mix in the 5 mould and around the core whereby the enamel or finishing material will be transferred from the core to the mix to form a finished wall of the stone casting.

2. The method of casting a stone casting which consists in applying a parting material to the core, covering the core with an enamel, or finishing material, applying a filler to the enameled surface of the core, and then pouring the mix in the mould and around the core whereby the filler and enamel surface of the-core may be transferred to the surface of the stone casting whose contour is formed by the core.

3. The method of making a cabinet which includes a cast stone portion fora refrigerator orthe like, which comprises utilizing a mold and a core for the forming of the cast stone portion from a plastic mix, the core being adapted to form a chamber and adapted to be removed to expose the stone walls of the chamber, applying a parting material to the core, coating the core with a finishing material prior to the pouring of the mix, which finishing material is transferred to the cast stone to form an exposed finish therefor upon removal of the core. 4. The method of making a cabinet which includes a cast stone portion for a refrigerator or the like, which comprises utilizing a mold and acore for the forming of the cast stone portion from a plastic mix, the core being adapted to form a chamber and adapted to be removed to expose the stone walls of the chamber, applyin a parting material to the core, applying a %nishing material over this parting material in the core and then a plying a filler over this finishing material, a 1 prior to the pouring of the mix, and all of which are transferred to the cast stone uponremoval of the core, whereby the filler smooths and fills irregularities in the cast stone and the finishing material forms an exposed finish for the stone casting.

In testimony whereof I'have aflixed my signature.

LLOYD G. COPEMAN.

1. The method of making a stone casting 

